The present invention relates generally to compressor systems and, more particularly, to air compressor systems.
Conventional air compressors typically include a compressor, a motor to drive the compressor and an air and oil cooling system to cool the compressed air and lubricating oil. Conventional air compressors are usually enclosed within a housing. A blower, fan or the like draws air into or pushes air through an opening in the housing. Some of the air which enters the housing is drawn into the compressor for ultimate use and the remaining portion of the air passes through the housing to cool the compressor, the motor, the air and oil cooling system, and other components before being discharged from the housing.
FIG. 1 schematically illustrates a conventional compressor system 10. The compressor system 10 includes a housing 14 having an air intake opening 18 and an air outlet opening 22. A compressor (i.e., airend) and a motor or drive train operatively connected to the compressor are housed within the housing 14. A fan 26 is positioned downstream from the airend of the compressor and motor to draw air in through the air intake opening 18. Some of the air drawn into the housing is compressed in the airend of the compressor and some of the air flows over the compressor and motor to cool the compressor and motor. The fan 26 also pushes the air through a plenum box 30 which is used to distribute the air over an air and oil cooler 34 before pushing the air out of the air outlet opening 22.
A problem with the known compressor system described above is the large amount of noise that emanates from the openings in the housing. The air flowing through the housing to cool the compressor and motor flows, for the most part, in a linear path from the air intake opening in the housing through the air outlet opening in the housing. Noise generated by the compressor and motor is freely emitted through the openings in the housing because there is no significant obstruction or other sound reducing means within the housing to reduce the amount of noise which can be carried out of the housing. Thus, there is a need for a new compressor system that significantly reduces the amount of noise which emanates from air inlet and outlet openings provided in the compressor system housing.
A feature of the present invention is to provide a compressor system having a housing which includes separate compartments. A first compartment houses an air and oil cooling system for the compressed air and lubricating oil. A second compartment houses a compressor and motor which generate most of the operating noise of the compressor system. A large portion of air drawn in through an air intake opening of the housing is directed to cool the air and oil cooling system positioned in the first compartment. A smaller portion of air drawn in through the air intake opening of the housing is directed into the second compartment to cool the compressor and motor. According to the principles of the present invention and contrary to conventional wisdom, it has been determined that only a small portion of the air drawn into the housing is actually needed to sufficiently cool the compressor and motor. Thus, the second compartment is substantially closed, except for a first limited opening to allow the required amount of cooling air in and a second limited opening to allow the cooling air to exit. The compressor and motor are substantially isolated from the air intake opening and air outlet opening in the housing, thereby reducing the amount of noise generated by the compressor and motor that would normally emanate out such openings. Limiting the amount of cooling air which flows over the noise generating compressor and motor also reduces the amount of air-born noise which can exit out of the openings of the housing.
Another feature of the present invention is to provide a compressor system which regulates the amount of air fed to the compression chamber of a compressor, the amount of air used to cool an air and oil cooling system for the compressed air and lubricating oil, and the amount of air which cools the compressor and motor, all for the purpose of reducing the amount of noise emitted from an air intake opening and an air outlet opening in the housing of the compressor system. Thus, the present invention provides in one aspect thereof, an air directing device which receives a stream of air flowing through an air intake opening in the compressor system housing. A portion of air drawn in through the air intake opening of the housing is caused to cool the air and oil cooling system for the compressed air and lubricating oil. Another portion of air drawn in through the air intake opening of the housing is separated into two streams of air by the air directing device. The first separated stream of air is fed to a compression chamber of the compressor. The second separated stream of air is directed through a non-linear path to flow over the compressor and motor to cool the compressor and motor, and then out of the air outlet opening in the housing. Because only a small portion of the air entering the compressor system housing is actually used to cool the compressor and motor, and because the air used to cool the compressor and motor travels in a non-linear path through the compressor housing, the amount of noise generated by the compressor and motor that emanates from the openings in the compressor housing is greatly reduced, as compared to conventional compressor systems.
Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings in which like numerals are used to designate like features.